In recent years, a control system (EMS: Energy Management System) including an equipment control apparatus which is installed in a power consumer's facility and controls a plurality of pieces of equipment has drawn attention. A communication protocol capable of enabling the equipment control apparatus to control the equipment provided by various makers is introduced to the system.
As one of the communication protocol, ECHONET Lite (registered trademark) defines an equipment class for every type of the equipment and defines information and control objects of the equipment as properties for every equipment class. For example, a storage battery apparatus belongs to a storage battery class, and properties corresponding to the storage battery class include a storage battery capacity, maximum and minimum charge power values, or the like (see Non Patent Literature 1).
On the other hand, a power feed system which includes a power control apparatus (power conditioner) capable of collectively converting DC power output by each of a plurality of power supply apparatuses to AC and supplies AC power to a load has been studied to be introduced. The plurality of power supply apparatuses is a solar power generation apparatus, a storage battery apparatus, a fuel cell apparatus, and the like.
The above-described power feed system is a new system using a combination of a plurality of power supply apparatuses and has features which do not exist in a system in the related art using a single power supply apparatus.
For example, a storage battery apparatus is charged in a state that DC power output by a solar power generation apparatus is maintained to be DC, so that it is possible to reduce a power conversion loss in comparison with a system in the related art which performs DC-AC conversion in a power supply apparatus.
However, since the above-described communication protocol considers only the system in the related art using a single power supply apparatus, it is difficult to perform efficient control in the case of using a combination of a plurality of power supply apparatuses.